Seventh-day Adventists are a health-oriented religious group with a conservative lifestyle who do not smoke or drink by church proscription. Among Adventists, mortality for many cancer sites which are unrelated to smoking is 50-80% of the general population. The Adventist Church strongly discourages the use of coffee and highly refined foods and they also strongly recommend many health promoting practices including a lacto-ovo-vegetarian diet, which is low in saturated fat and high in dietary fiber, retinoids and vitamin C. However, there is great variation in the degree of adherence to these habits among Adventists. This variation can be defined, measured accurately, and validated; which makes Adventists an ideal population in which to investigate the role of diet and other lifestyle characteristics in cancer risk. Furthermore, the great variation in duration of exposure, and age at first exposure, to the Adventist lifestyle provides a unique opportunity to determine the relative effect of lifestyle patterns early versus late in life. In broad terms, this study seeks to (1) identify the specific elements of lifestyle that relate to risk of specific cancers within the Adventist population, (2) to identify interactions among lifestyle factors which relate to cancer, and (3) to compare the risk of specific cancers between Adventists and the general population. The data collection for phase one of this prospective study is now virtually complete. Ascertainment of an estimated 1,246 newly diagnosed cancer cases will be completed within 6 months. Baseline data on demographic characteristics from 59,202 California Adventists, as well as detailed lifestyle characteristics from 40,347 of these subjects will be used for 2 years of in-depth analyses of specific a priori hypotheses regarding the relationship of lifestyle traits to risk of specific cancer sites. The analysis plan will utilize stratified analysis, the Poisson regression model for grouped data, and Cox proportional hazards model. These analyses are likely to identify new (or confirm previously suspected) lifestyle characteristics at risk factors, or protective factors, for cancer.